Frontiers in Psychiatry
May 21, 2020
Morgana M. Novaes, Fernanda Palhano-Fontes, Heloisa Onias et al.
110 citations
Four weeks of Bhastrika pranayama, a yoga breathing exercise, significantly reduced anxiety and negative affect in thirty healthy young adults. Brain scans showed that the practice modulated activity in emotion-processing regions including the amygdala, anterior cingulate, anterior insula, and prefrontal cortex, and decreased functional connectivity between the anterior insula and lateral prefrontal cortex. Changes in connectivity between the ventrolateral prefrontal cortex and right anterior insula correlated with changes in anxiety. The authors note these analyses were preliminary and exploratory.
Frontiers in Psychiatry
December 5, 2022
Geovan Menezes de Sousa, Vagner Deuel de Oliveira Tavares, Ana Cecília de Menezes Galvão et al.
14 citations
In a double-blind, placebo-controlled trial with 72 participants, ayahuasca's effects on depression-related biomarkers were examined two days after dosing. Larger reductions in depressive symptoms during the session were linked to higher serum cortisol levels in patients with treatment-resistant depression. Smaller changes in salivary cortisol during ayahuasca use were associated with higher brain-derived neurotrophic factor (BDNF) levels in patients who showed greater clinical improvement in depressive symptoms. No moderating effects were found for the cortisol awakening response, interleukin-6, or C-reactive protein in patients, nor for any biomarker in healthy controls or the placebo group. The findings suggest that acute emotional and physiological responses during ayahuasca sessions may influence key biomarkers of depression.
Journal of ethnopharmacology
February 10, 2024
Tiago Arruda Sanchez, Lucas Rego Ramos, Felipe Araujo et al.
12 citations
Ayahuasca, a traditional Amazonian beverage, attenuates brain activity in the amygdala—a region central to fear processing—when people view aversive (fearful or disgusted) faces, while enhancing activation in the insular cortex and right dorsolateral prefrontal cortex. Nineteen experienced male users underwent fMRI before and 50 minutes after ingesting ayahuasca. Self-reported anxiety and mental sedation also decreased. The findings suggest ayahuasca may promote emotion regulation in response to negative stimuli, with corresponding improvements in cognition.
Frontiers in behavioral neuroscience
January 1, 2022
Maria Lara Porpino de Meiroz Grilo, Geovan Menezes de Sousa, Lilían Andrade Carlos de Mendonça et al.
12 citations
Repeated ayahuasca administration before and during social isolation prevented depressive-like behaviors and cortisol alterations in common marmosets. Animals given ayahuasca showed higher cortisol reactivity and fecal cortisol levels similar to family-group controls, no signs of anhedonia, and no increase in chronic stress-related behaviors, unlike isolated animals that received no intervention. The findings suggest ayahuasca promotes resilient responses and may have a prophylactic action against depression.
Nature communications
August 13, 2025
William Wong, Rubén Herzog, Kátia Cristine Andrade et al.
10 citations
A new open database, the DREAM database, combines standardized sleep magneto/electroencephalography (M/EEG) recordings with dream reports from 505 participants across 20 datasets, totaling 2,643 awakenings. Each awakening includes at least 20 seconds of high-resolution sleep EEG (≥100 Hz, ≥2 electrodes) and a classification of the sleeper's reported experience. Analyses showed that reports of conscious experiences during sleep can be predicted from objective EEG features in both REM and NREM sleep. The database aims to overcome limitations of small sample sizes and methodological variability in dream research, enabling larger-scale investigations of the neurocognitive basis of dreaming.
Journal of psychiatric research
August 1, 2024
Eduardo Igor Torquato Cardoso Lopes, Patrícia Cavalcanti-Ribeiro, Fernanda Palhano-Fontes et al.
9 citations
Subcutaneous esketamine injections given weekly for eight weeks produced a rapid and lasting reduction in suicidality among 18 adults with treatment-resistant depression. Suicidal thoughts dropped within 24 hours after the first dose and remained low throughout the eight-week treatment period. At six months after treatment ended, suicidality was still consistently lower. Clinician ratings showed significant improvement only after two sessions, and 61% of patients achieved remission from suicidal ideation. The findings suggest that weekly subcutaneous esketamine may be a cost-effective way to achieve fast and sustained anti-suicide effects, but controlled studies are needed to confirm these initial observations.
January 1, 2019
Draulio Barros de Araujo
7 citations
Ayahuasca, a traditional psychedelic brew, significantly impacts psychological well-being, with 75% of participants reporting improved mental health outcomes in a study of 200 individuals. The effects are attributed to its influence on neurotransmitter receptors, which may alter behavior and emotional states. Biochemical analysis revealed that ayahuasca enhances serotonin receptor activity, potentially leading to lasting changes in mood and cognition. These findings contribute to the growing body of evidence supporting the therapeutic potential of psychedelics in addressing mental health challenges.
European archives of psychiatry and clinical neuroscience
October 28, 2024
Kaike Thiê da Costa Gonçalves, Vagner Deuel O de Tavares, Maria Luiza de Morais Barros et al.
5 citations
A systematic review of 29 studies examined whether the psychoactive effects of ketamine are linked to its therapeutic benefits for psychiatric disorders. About half of the studies (51.72%) found a positive relationship between ketamine-induced altered states of consciousness and clinical outcomes, while 44.83% found no link, and one study found a negative association. For mood disorders like major depressive disorder and bipolar disorder, 48% of studies showed a positive relationship and 48% showed none. All three studies on substance use disorder reported a positive correlation. The authors conclude the relationship remains uncertain due to high variability across studies.
European Archives of Psychiatry and Clinical Neuroscience
March 28, 2026
Yves Martins Varela, Vagner Deuel De O. Tavares, Luiza Macedo Delgado et al.
1 citation
Cognitive-behavioral therapies are being combined with psychedelic substances such as ketamine, psilocybin, and MDMA to treat mental disorders, but the way they are integrated varies widely across studies. A systematic review of 9 clinical trials involving 283 patients found that traditional cognitive behavioral therapy was the most common approach, used in 6 studies, while mindfulness-based cognitive therapy and acceptance and commitment therapy were each used in 2 and 1 studies respectively. The timing of therapy relative to the psychedelic experience—before, during, or after—also differed. The findings highlight the need for more consistent research to clarify how these therapeutic models are best implemented.
Journal of clinical psychopharmacology
Vagner Deuel de O Tavares, Kaike Thiê da Costa Gonçalves, Maria Luiza de Morais Barros et al.
1 citation
A meta-analysis of eleven studies found no significant correlation between the psychoactive (psychomimetic) effects of ketamine and clinical outcomes in mental illness, including depression. The overall correlation was r = 0.06, and for depression specifically r = 0.03, both non-significant. Sub-analyses accounting for patient disorders, intravenous administration, assessment instruments, and timing also yielded no significant findings. High heterogeneity was present. The analysis suggests that altered states of consciousness during ketamine sessions are not directly linked to clinical outcomes, but the limited number of studies and heterogeneity make this conclusion preliminary.
medRxiv Preprint Server
May 31, 2026
Yves Martins Varela, Patrícia Cavalcanti-Ribeiro, Geovan Menezes de Sousa et al.
preprint
Ketamine rapidly reduces depression symptoms in treatment-resistant depression, but its effects may be enhanced by combining it with psychotherapy. The drug induces neuroplasticity and psychological openness, which could help patients process emotions, restructure thoughts, and maintain improvements. However, research has not yet thoroughly examined whether adding structured psychotherapy to ketamine treatment provides additional benefits.
Journal of affective disorders
March 15, 2026
Patrícia Cavalcanti-Ribeiro, Lara Carvalho Araújo Melo De Souza, Vagner Deuel O de Tavares et al.
In a small open-label trial of 22 patients with treatment-resistant depression who received seven weekly subcutaneous doses of esketamine, those with elevated baseline C-reactive protein (CRP > 1 mg/L) showed significant reductions in CRP by week 4 and week 8, while patients without inflammation showed no change. By week 8, CRP levels in both groups were comparable. Although the inflammation group had a greater average reduction in depression severity (15.88 points on the MADRS scale versus 11.14 points), this difference was not statistically significant, and changes in CRP did not predict symptom improvement. Larger controlled studies are needed.